If you want to get the biggest buffer and over 1000 shots with the 20mP images for your D5 you will need a 64 gB card. I can shoot 1000 shots for a show. I really don't want to go to overflow or change a card.
I bought a Lexar which was, then cheapest/fastest. I use a 32 gB card for overflow. I never shoot back up cards and, in 10 years, have never had a card failure of any brand.
